High frequency transistor ballast

Abstract

A high frequency transistor ballast is utilized to drive flourescent lamps. The electrical system of the ballast consists of a central rectifying and control panel and a high frequency inverter. There is also provided a low energy switch in the high frequency inverter system controlling the operation of the high frequency transistor ballast.

What is claimed is: 
     
       1. A power source for supplying low pressure discharge lamps comprising: a. ballasting means connected to said lamps and to windings of a transformer,   b. a direct current source,   c. inverting means connected to said direct current source to produce high frequency alternating current including a plurality of active devices connected to other windings of said transformer, a frequency controlling device and a low voltage energy limited remote control means magnetically coupled to said inverting means for disabling said inverting means.   
     
     
       2. The power source of claim 1 in which said frequency controlling device is a saturable transformer connected to said active devices and said low voltage energy limited remote control means includes a winding on said saturable transformer. 
     
     
       3. The power source of claim 1 in which said low voltage control means includes a switch for disabling said inverting means, when closed. 
     
     
       4. The power source of claim 1 wherein said inverting means includes a pair of SCR's. 
     
     
       5. The power source of claim 1 wherein said inverting means includes a push-pull transistor oscillator having at least a pair of transistors. 
     
     
       6. The power source of claim 5 in which said inverting means includes a starting circuit including a diac to supply current pulses to the base of one of said transistors to drive that transistor into saturation to start said oscillator. 
     
     
       7. The power source of claim 5 including a saturable transformer connected between the bases of said transistors. 
     
     
       8. The power source of claim 7 in which said low voltage control means includes another winding on said saturable transformer connected to a remote switch for disabling said inverter when said switch is closed. 
     
     
       9. The power source of claim 8 wherein said remote switch is connected via low gauge conductors. 
     
     
       10. A remotely controlled power inverter in which a switch means, remote from said inverter, is connected thereto with low gauge conductors comprising; a. a source of direct current,   b. a pair of active devices powered by said source,   c. a saturable transformer including a first winding connected between the control of electrodes of said active devices,   d. a second winding of said transformer connected to said switch means by said low gauge conductors whereby a low impedance is reflected into said first winding to shunt current from said control electrodes to inhibit operation of said inverter when said switch is closed.